This invention relates to reciprocating cylinder valves to drive self-propelled sprinkler systems and the like. More particularly, this invention relates to a self-contained reciprocating cylinder assembly for the propulsion of sprinkler systems and the like by hydraulic means.
Self-propelled sprinkler irrigation systems are well known in the art. Such systems have been developed to carry long lengths of conduit pipe. Usually lengths of pipe will be supported at various intervals by towers which consist of a framework mounted on wheels which are self-propelled by various means. These sprinkling systems ordinarily will cover a quarter section of land, and as such, the pipe or conduit may be as long as 1320 feet. Various methods have been proposed to propel the towers to keep the pipe or conduit in alignment and when the pipe or conduit bends, either by lagging behind or getting too far ahead, responsive means will actuate a hydraulically or electrically driven system which will cause the towers to speed up or slow down so as to remain substantially in alignment.
Normally, such sprinkler systems move in a circular motion around a pivotal point containing the water source, and the movement or motion of each tower must be separately regulated. Means are disclosed in U.S. Pat. Nos. 3,386,661 and 3,766,937 for hydraulically actuating a bar which interconnects lugs associated with the wheels on the tower. These bars contain hooks which engage with the lugs in response to the reciprocating motion of a cylinder thereby causing the tower wheels to move the distance between the lugs associated with the tower wheels upon each reciprocating movement of the cylinder.
In U.S. Pat. No. 3,386,661 the hydraulic system is an enclosed system which extends along the entire length of the irrigating conduit, and the hydraulic fluid is powered or compressed by means of a single pump. In U.S. Pat. No. 3,766,937 there is an individual drive or self-contained fluid system associated with each tower. In each of these patents, however, the drive means at each tower is provided by a double-action, hydraulically actuated piston.